KillTheTwit

// ==UserScript==
// @name           KillTheTwit
// @include        http://www.exiern.com/*
// @include        http://www.bloomingfaeries.com/*
// ==/UserScript==

var results = document.evaluate(
    "//li[div[@class=\"comment-content\"]/div/cite/text()=\"Guesticus\"]",
    document, null, XPathResult.UNORDERED_NODE_SNAPSHOT_TYPE, null);

for (var i = 0; i < results.snapshotLength; i++) {
    results.snapshotItem(i).getElementsByClassName('comment-text')[0].textContent = "*** Twit filtered ***";
}